Soft tissue conduit device

ABSTRACT

A method of conducting biological materials to soft tissue. The method includes loading a conduit device onto a delivery shaft of an inserter, inserting at least a portion of the delivery shaft into soft tissue, expelling the conduit device from the delivery shaft into the tissue, and delivering biological material through an access port of the inserter into at least one outer longitudinal channel of the conduit device.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation-in-part of U.S. patent applicationSer. No. 11/408,282, filed on Apr. 20, 2006 now abandoned, which is acontinuation-in-part of U.S. patent application Ser. No. 11/347,661filed on Feb. 3, 2006 now U.S. Pat. No. 7,749,250, and this applicationis also a continuation-in-part of U.S. patent application Ser. No.11/294,694 filed Dec. 5, 2005 now U.S. Pat. No. 7,914,539, which is acontinuation-in-part of U.S. patent application Ser. No. 10/984,624filed Nov. 9, 2004 U.S. Pat. No. 7,608,098. The disclosures of the aboveapplications are incorporated herein by reference.

INTRODUCTION

Tears caused by trauma or disease in soft tissue, such as cartilage,ligament, or muscle, can be repaired by suturing and/or use of variousfixation devices. Various tissue fixation devices have been developedfor facilitating suturing and are effective for their intended purposes.

Although the existing soft tissue fixation devices can be satisfactoryfor their intended purposes, there is still a need for new devices andmethods of conducting biological materials to soft tissue.

SUMMARY

The present teachings provide a method of conducting biological materialto soft tissue. The method includes loading a conduit device onto adelivery shaft of an inserter, inserting at least a portion of thedelivery shaft into soft tissue, expelling the conduit device from thedelivery shaft into the tissue, and delivering biological materialthrough an access port of the inserter into at least one outerlongitudinal channel of the conduit device.

The present teachings further provide a method of conducting biologicalmaterial to soft tissue that includes loading at least first and secondconduit devices onto a delivery shaft of an inserter, inserting at leasta portion of the delivery shaft into a first location in soft tissue,expelling the first conduit device from the delivery shaft into thetissue, delivering biological material through an access port of theinserter into an outer longitudinal channel of the first conduit device,and removing the delivery shaft from the tissue.

The present teachings provide a method of conducting biological materialto meniscal tissue. The method includes making an arthroscopic incisionin a knee, exposing meniscal tissue, loading a first conduit device ontoa delivery shaft of an inserter, optionally loading a second conduitdevice onto the delivery shaft of the inserter; inserting at least aportion of the delivery shaft into a first location in the meniscaltissue, expelling the first conduit device from the delivery shaft intothe meniscal tissue between two areas of different vascularity,delivering biological material through an access port of the inserterinto at least one outer longitudinal channel of the first conduitdevice, removing the delivery shaft from the meniscal tissue, optionallyinserting the delivery shaft of the inserter into a second location inthe meniscal tissue, optionally expelling the second conduit device fromthe delivery shaft into the meniscal tissue, optionally deliveringbiological material from the inserter into at least one outerlongitudinal channel of the second conduit device, removing the deliveryshaft of the inserter from the meniscal tissue, and closing theincision.

Further areas of applicability of the present invention will becomeapparent from the description provided hereinafter. It should beunderstood that the description and specific examples are intended forpurposes of illustration only and are not intended to limit the scope ofthe invention.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will become more fully understood from thedetailed description and the accompanying drawings, wherein:

FIG. 1A is an isometric view of a conduit device according to thepresent teachings;

FIG. 1B is a side view of the conduit device of FIG. 1A;

FIG. 1C is an end view of the conduit device of FIG. 1A;

FIG. 1D is an end view of a conduit device illustrating adequate tentingof soft tissue according to the present teachings;

FIG. 1E is an end view of a conduit device illustrating inadequatetenting of soft tissue;

FIG. 2A is an isometric view of a conduit device according to thepresent teachings;

FIG. 2B is a side view of the conduit device of FIG. 2A;

FIG. 2C is an end view of the conduit device of FIG. 2A;

FIG. 3A is an isometric view of a conduit device according to thepresent teachings;

FIG. 3B is a side view of the conduit device of FIG. 3A;

FIG. 3C is an end view of the conduit device of FIG. 3A;

FIG. 4A is an isometric view of a conduit device according to thepresent teachings;

FIG. 4B is a side view of the conduit device of FIG. 4A;

FIG. 4C is an end view of the conduit device of FIG. 4A;

FIG. 5 illustrates a method of inserting a conduit device in soft tissueaccording to the present teachings;

FIG. 6A is an isometric view of a conduit device according to thepresent teachings;

FIG. 6B is a side view of the conduit device of FIG. 6A;

FIG. 6C is an end view of the conduit device of FIG. 6A;

FIG. 7A is an isometric view of a conduit device according to thepresent teachings;

FIG. 7B is a side view of the conduit device of FIG. 7A;

FIG. 7C is an end view of the conduit device of FIG. 7A;

FIG. 8A illustrates a method of connecting two conduit devices with twofixation devices according to the present teachings;

FIG. 8B illustrates a method of connecting two conduit devices with twofixation devices according to the present teachings;

FIG. 9 illustrates a method of repairing a meniscal tear according tothe present teachings;

FIG. 10A is an isometric view of a conduit device according to thepresent teachings;

FIG. 10B is an isometric view of a conduit device according to thepresent teachings;

FIG. 11A is an isometric view of a conduit device according to thepresent teachings;

FIG. 11B is a side view of the conduit device of FIG. 11A;

FIG. 11C is an end view of the conduit device of FIG. 11A;

FIG. 12A is an isometric view of a distal portion of an inserteraccording to the present teachings, shown pre-loaded with two conduitdevices;

FIG. 12B is an isometric view of the proximal portion of the inserter ofFIG. 12A; and

FIGS. 13A-13D illustrate aspects of an exemplary method of inserting oneor more conduit devices in meniscal tissue according to the presentteachings using the inserter of FIG. 12A.

DESCRIPTION OF VARIOUS ASPECTS

The following description is merely exemplary in nature and is in no wayintended to limit the invention, its application, or uses. For example,although the present teachings are illustrated for repairing meniscaldefects in knee surgery, the present teachings can be used to repair andfacilitate healing or regeneration of any injured soft tissue.

Referring to FIGS. 1A-C, an exemplary soft tissue conduit device 100according to the present teachings includes an elongated body 102 havingan outer surface 104 and a plurality of longitudinal external channels106 extending along the entire length of the body 102. The channels 106are shaped such that when the conduit device 100 is inserted into softtissue, the channels 106 can serve as conduits for conducting biologicalmaterials, such as nutrients, into the tissue from outside the tissue orbetween first and second areas of the tissue, such as, for example,between healthy tissue and injured or torn tissue, or between areas ofdifferent vascularity, such as between red-red (vascular), red-white(semi-vascular) and white (avascular) tissue areas of a meniscus. Thechannels 106 can provide a vascularity path in the tissue forfacilitating healing or repair. As such, each channel 106 can have awidth “w” and a depth “d” that allows the tissue to envelope or form a“tent” over the channel 106 without blocking the channel 106. Referringto FIG. 1D, deep channels 106 exemplify a shape that providessatisfactory “tenting” or draping of tissue 80 over the channels 106.Referring to FIG. 1E, shallow channels 106′ illustrate inadequatetenting of tissue 80 over the channels 106′, with the tissue at leastpartially entering the channels 106′. Satisfactory tenting of tissue 80allows unobstructed or relatively unrestricted flow of nutrients orother biological materials along the channels 106. Typical aspect ratiosd/w are less than 1, such as, for example, 0.5, 0.8, etc.

Various biological materials can be delivered through the channels 106by external cannulas or other pumping devices during or afterimplantation. Such biological materials can be in the form ofautologous, allogenic, xenograpt or recombinant cells and factorsderived from blood, bone marrow aspirate, or fat containing variousgrowth factors, stem cells, activators with or without adhesiveproperties. Native or endogenous biological materials can also becarried after implantation from a vascular region of the soft tissue 80to the injured site by inserting the conduit device 100 such that theconduit device 100 extends from a vascular region of the soft tissue tothe injured site. Additionally or alternatively, biological materials inthe form of platelet gels can be deposited in the channels 106 beforeimplantation, as another mechanism of biological material delivery,including nutrient, delivery.

Referring to FIGS. 1A-1C, the body 102 of the conduit device 100 caninclude a cylindrical portion 108 of constant dimensions and a taperedportion 110. The body 102 can also include a plurality of blunt,rounded, and generally non-cutting ridges or threads 112 that areinterrupted by the channels 106. The body 102 can be cannulated with aninternal longitudinal bore 114. The longitudinal bore 114 can include aplurality of facets 116 for engaging a driver or other inserter forinserting the conduit device 100 in the soft tissue 80. The bore 114 canhave, for example, a square, triangular, hexagonal or other shapeconfigured to engage the driver non-rotatably.

Referring to FIGS. 1A-1C, 2A-2C, and 3A-3C, exemplary conduit devices100 having channels 106 with rounded V-shaped cross-sections areillustrated. FIGS. 1A-1C illustrate an aspect of the conduit device 100with four channels 106 arranged, for example, symmetrically relative tothe four sides 116 of a square bore 114, although asymmetricalarrangements can also be used. FIGS. 2A-2C illustrate an aspect of theconduit device 100 with six channels 106 arranged symmetrically relativeto the four sides 116 of the square bore 114. FIGS. 3A-3C illustrate anaspect of the conduit device 100 with five channels 106 arrangedasymmetrically relative to the four sides 116 of a square bore 114.

Referring to FIGS. 4A-4C, an exemplary conduit device 100 havingchannels 106 with keyhole-shaped cross-sections is illustrated. Thekeyhole shape can include a substantially circular portion 118 and anarrow slot-like opening 120 to the outer surface 104 of the body 102.The keyhole shape can be used to provide a path for substantial volumeof biological materials or nutrients with good tenting of tissue 80 overthe channels 106. It will be appreciated, however, that a differentnumber of channels 106 and a variety of different channel shapes can beused as conduits for the conduit device 100.

Referring to FIG. 5, an exemplary method of using the conduit device 100is illustrated. A driver 130 can be used to insert the conduit device100 through a tear or other defect or injury 82 in the soft tissue ormeniscus 80. The driver 130 can have a shaft 132 configured to engagethe bore 114 of the body 102 of the conduit device 100 to facilitateinserting and guiding the conduit device 100 into the tissue 80. Theshaft 132 of the driver 130 can also include a sharp tip 134 forfacilitating the insertion of the conduit device 100 into tissue 80. Thedriver 100 can be used to rotate the conduit device 100 such that theblunt threads 112 push the tissue 80 aside during the insertion theconduit device 100. The conduit device 100 can be used to connect areasof good vascularity 84 of the soft tissue 80, such as, for example, theouter surface of a meniscus, with the site of the defect 82 or otherareas of low or no vascularity, and can also serve as a fixation devicethat can bridge the defect 82 and or and bring closer together oppositesites of torn or damaged tissue at the defect 82.

Referring to FIGS. 6A-6C and 7A-AC, the conduit device 100 can have abody 102 with a substantially cylindrical shape of constant diameterwithout external threads or ridges, and having an outer surface 104interrupted by a plurality of longitudinal channels 106. The body 102can be otherwise solid (non-cannulated) as illustrated in FIGS. 6A-6C,or cannulated with an internal longitudinal bore 114, as shown in FIGS.7A-7C. The channels 106 can have different cross-sectional shapes,including the illustrated keyhole shapes for improved tissue tenting.The non-threaded conduit devices 100 of FIGS. 6A-6C and 7A-AC can beused with various anchors, buttons, toggles or other fixation devices140, as illustrated in FIGS. 8A-B and 9.

Referring to FIGS. 10A and 10B, exemplary conduit devices 100 havingflat or parallelepiped bodies are illustrated. The channels 106 can besquare or V-shaped or U-shaped or key-hole shaped, for example. Theconduit devices 100 can include central bores 114 or can be solid. Itwill be appreciated that conduit devices 100 of various other shapes canbe used, such as oval, square, rectangular, circular, or other shapes,and having channels 106 of different shapes. Referring to FIGS. 11A-C,an exemplary threaded conduit device 100 having a solid ovalcross-section with outer longitudinal channels 106, a tapered portion110 and a cylindrical portion 108 is illustrated. The oval cross-sectioncan provide a lower profile while maintaining a satisfactory strengthand size for the function of the conduit device 100. It will beappreciated that the conduit device 100 of FIGS. 11A-C can also becannulated.

The conduit devices 100 can be coupled with fixation devices 140 usingsutures or flexible strands 142 passing through the central bore 114 orthrough two channels 106, as discussed below in reference to FIGS. 8A-B.Referring to FIG. 8A, two cannulated conduit devices 100 a, 100 b can becoupled with corresponding fixation devices 140 a, 140 b using a sutureor other elongated flexible strand 142. The flexible strand 142 candefine a loop that passes through the first bore 114 a, connects to thecorresponding fixation device 140 a, returns through the same bore 114a, passes through the second bore 114 b, connects to the second fixationdevice 140 b, returns through the second bore 114 b, and closes the loopwith a knot, button or other retainer 144.

Similarly, two non-cannulated conduit devices 100 a, 100 b can becoupled with corresponding fixation devices 140 a, 140 b using theflexible strand 142, as shown in FIG. 8B. The flexible strand 142 candefine a loop that passes through a first external channel 106 a of thefirst conduit device 100 a, connects to the corresponding fixationdevice 140 a and returns through a second channel 106 b of the firstconduit device 100 a. The flexible strand 142 then passes through athird channel 106 c of the second conduit device 100 b, connects to thesecond fixation device 140 b, returns through a fourth channel 106 d ofthe second conduit device 100 b, and closes the loop with a retainer144.

Referring to FIG. 9, two conduit devices 100 are shown coupled with twofixation devices 140, which are inserted through a tear 82 in a meniscusand secured by tightening the loop defined by the flexible strand 142.The implantation of the conduit devices 100 and the fixation devices 140for reducing or closing the tear 82 can be performed according to themethods described in co-pending parent patent application Ser. No.11/347,661 filed Feb. 3, 2006, and incorporated herein by reference.

Referring to FIGS. 12A and 12B, an exemplary inserter 150 for theconduit devices 100 is illustrated. The inserter 150 can include agripping handle 152, a slider 154 operating a pusher rod 156, and anaccess port 160 communicating with a delivery shaft 158, such as ahypodermic tube or surgical needle, for example. The delivery shaft 158has a bore 159 adapted to receive a conduit device 100 therein. One ormore conduit devices 100 can be loaded serially in the delivery shaft158 for successive deployment selectively in various soft tissuelocations. The delivery shaft 158 can include a sharp tip 162 forpiercing soft tissue. The access port 160 can be in the form of a luerlock or can include a luer lock 164 for quick connection with a deliverydevice 170, such as a syringe or cannula or pumping device. The accessport 160 and delivery device 170 can be perpendicular to the deliveryshaft 158, as shown in FIGS. 12A and 13B. The access port 160 can beused to deliver nutrients or other biological materials to the conduitdevice or devices 100 during insertion and while the devices 100 areinside the delivery shaft 158. As discussed above, however, the conduitdevices 100 can also be coated with nutrients prior to or at the time ofdelivery into tissue.

The slider 154 of the inserter 150 can be operated to move the pusherrod 156 into the delivery shaft and cause sequential expulsion of theconduit devices 100. The handle 152 can incorporate a double click orother sound mechanism to alert the operating surgeon that a proper depthinto tissue has been achieved and that the conduit device 100 has beendelivered out of the delivery shaft 158 and into the tissue.

Referring to FIGS. 13A-13D, an exemplary procedure for vascularizationof meniscal tissue 80 is illustrated. With the knee in flexion, anarthroscopic incision 60 is made and held open to expose the meniscus80, as shown in FIG. 13A. One or more conduit devices 100 can beinserted into the meniscus 80 to connect a vascular region 84 of themeniscus with a less vascular or avascular region, such as a defect ortear 82, or other less vascular or weak region, as discussed above. Inan illustrative procedure, the delivery shaft 158 of the inserter 150can be loaded with one or more conduit devices 100. The inserter 150 canpierce the meniscal tissue 80 to deliver a first conduit device 100,such that the first conduit device 100 extends between the vascularregion 84 and the defect or weak region 82, as shown in FIG. 13B.Biological material can be delivered through the access port 160 intothe channels 106 of the conduit device 100 before, during or after theinsertion of the conduit device 100 into the tissue. For example,although biological material can be delivered to the conduit device 100while the conduit device 100 is still inside the delivery shaft 158, theconduit device 100 can also be expelled from the delivery shaft 158, andwhile the delivery shaft 158 is still attached to tissue, biologicalmaterial can be delivered from the delivery shaft 158 through tissue tothe channels 106 of the conduit device 100. The delivery shaft 158 canthen be removed from the meniscal tissue 80 and, if it is determinedthat insertion of a second conduit device 100 is desirable, the deliveryshaft 158 can be re-inserted into the meniscal tissue 80 in anotherlocation for inserting a second conduit device 100 into the tissue andthen delivering biological materials into the tissue and through theconduit device 100, as shown in FIGS. 13C and 13D. It will beappreciated that although insertion of the conduit devices 100 isillustrated from the less vascular region or defect 82 toward the morevascular region 84, the conduit devices 100 can be alternativelyinserted in an opposite manner from the vascular region 84 to the lessvascular region or defect 82, depending on the particular procedure,location of defect or other considerations by the operating surgeon.

Further will be appreciated from the above description that the conduitdevices 100 can be used for many applications in which biologicalmaterials or nutrients are needed to be delivered to a soft tissue siteor transferred from one tissue site to another. The longitudinalchannels 106 of the devices coupled with dimensions that facilitatetenting of tissue 80 can provide unobstructed and uninterrupted orcontinuous paths for the flow or delivery of such biological materialsand nutrients across an interface in the tissue, such as, for example,across an interface between vascular and avascular regions, or across adefect, such as a tear or a weakened area, or across a healing site.Further, although certain aspects of the present teaching areillustrated in connection with certain figures, it should be appreciatedthat various aspects illustrated in the drawings can be selectivelycombined to provide a variety of embodiments. For example, in one suchcombination, the keyhole-shaped channels 106 shown in FIG. 4C can becombined with the oval cross-section of the conduits 100 shown in FIG.11C, replacing the channels 106 illustrated in FIG. 11C.

The foregoing discussion discloses and describes merely exemplaryarrangements of the present invention. One skilled in the art willreadily recognize from such discussion, and from the accompanyingdrawings and claims, that various changes, modifications and variationscan be made therein without departing from the spirit and scope of theinvention as defined in the following claims.

What is claimed is:
 1. A method of conducting biological material tosoft tissue, the method comprising: loading a conduit device having anouter surface onto a delivery shaft of an inserter; inserting at least aportion of the delivery shaft into soft tissue; expelling the conduitdevice from the delivery shaft into the tissue; connecting a deliverydevice to an access port of the inserter and to the delivery shaft ofthe inserter, the access port of the inserter positioned between thedelivery shaft and a handle of the inserter; and delivering biologicalmaterial from the delivery device through the access port of theinserter along the delivery shaft of the inserter and directly into andalong at least one outer channel of the conduit device that is at leastpartially open to the outer surface of the conduit device while theinserter is coupled to soft tissue and the conduit device is implantedin the tissue.
 2. The method of claim 1, wherein expelling the conduitdevice comprises pushing the conduit device with a pusher rod movablerelative to the delivery shaft of the inserter.
 3. The method of claim1, wherein inserting into soft tissue comprises inserting into meniscaltissue.
 4. The method of claim 1, further comprising delivering theconduit device across a defect in soft tissue.
 5. The method of claim 1,wherein delivering biological material comprises delivering biologicalmaterial from the delivery device through the access port of theinserter along the delivery shaft of the inserter and directly into afirst terminal end of the at least one outer channel.
 6. The method ofclaim 1, wherein delivering biological material comprises deliveringbiological material from the delivery device through the access port ofthe inserter along the delivery shaft of the inserter and directlyaxially into a first terminal end of the at least one outer channel ofthe conduit device, the first terminal end of the at least one outerchannel being co-planar with a first terminal end of the conduit device.7. The method of claim 6, wherein delivering biological materialcomprises delivering biological material from the delivery devicethrough the access port of the inserter along the delivery shaft of theinserter and directly axially into the first terminal end of the atleast one outer channel of the conduit device and along the at least oneouter channel to an oppositely located second terminal end of the atleast one outer channel, the oppositely located second terminal end ofthe at least one outer channel being co-planar with a second terminalend of the conduit device.
 8. A method of conducting biological materialto soft tissue, the method comprising: loading at least first and secondconduit devices each having a first terminal end, an oppositely locatedsecond terminal end and an outer surface onto a delivery shaft of aninserter; inserting at least a portion of the delivery shaft into afirst location in soft tissue; moving a pusher rod of the inserter bymoving a slider of the inserter; expelling the first conduit device fromthe delivery shaft into the tissue by the pusher rod; connecting asyringe to an access port of the inserter and perpendicularly to thedelivery shaft of the inserter, the access port of the inserterpositioned between the delivery shaft and a handle of the inserter;delivering biological material from the syringe through the access portalong the delivery shaft of the inserter directly into and along anouter longitudinal channel of the first conduit device that is at leastpartially open to the outer surface of the first conduit device andextends from the first terminal end to the oppositely located secondterminal end while the inserter is coupled to soft tissue and the firstconduit is implanted into the tissue; delivering the biological materialfrom and along the outer longitudinal channel from the first terminalend of the first conduit device to the oppositely located secondterminal end of the first conduit device to the soft tissue; andremoving the delivery shaft from the tissue.
 9. The method of claim 8,further comprising: inserting at least a portion of the delivery shaftinto a second location of the soft tissue; expelling the second conduitdevice from the delivery shaft into the tissue; delivering biologicalmaterial through the access port of the inserter directly into an outerlongitudinal channel of the second conduit device; and removing thedelivery shaft from the tissue.
 10. The method of claim 9, furthercomprising selectively inserting at least one of the first and secondconduit devices across an interface in the tissue, across a defect,across a healing site or between two areas of different vascularities ofthe tissue.
 11. The method of claim 9, wherein the soft tissue ismeniscal tissue, and further comprising inserting the first and secondconduit devices through a defect in the meniscal tissue.
 12. The methodof claim 8, wherein delivering biological material comprises deliveringbiological material from the syringe through the access port along thedelivery shaft of the inserter directly axially into a first terminalend of the outer longitudinal channel of the first conduit device, thefirst terminal end of the outer longitudinal channel being co-planarwith the first terminal end of the first conduit device.
 13. A method ofconducting biological material to meniscal tissue, the methodcomprising: making an arthroscopic incision in a knee; exposing meniscaltissue; loading a first conduit device having a first outer surface ontoa delivery shaft of an inserter; loading a second conduit device havinga second outer surface onto the delivery shaft of the inserter;inserting at least a portion of the delivery shaft into a first locationin the meniscal tissue; expelling the first conduit device from thedelivery shaft into the meniscal tissue between two areas of differentvascularity; connecting a delivery device with a luer lock to an accessport of the inserter and to the delivery shaft of the inserter, theaccess port of the inserter positioned between the delivery shaft and ahandle of the inserter; delivering biological material through theaccess port of the inserter directly into and along at least one outerlongitudinal channel of the first conduit device that is at leastpartially open to the first outer surface of the first conduit devicewhile the inserter is coupled to the meniscal tissue and the firstconduit is implanted into the meniscal tissue; removing the deliveryshaft from the meniscal tissue; inserting the delivery shaft of theinserter into a second location in the meniscal tissue; expelling thesecond conduit device from the delivery shaft into the meniscal tissueby moving a pushing rod of the inserter to a deployment position;delivering biological material from the inserter directly into and alongat least one outer longitudinal channel of the second conduit devicethat is at least partially open to the second outer surface of thesecond conduit device; removing the delivery shaft of the inserter fromthe meniscal tissue; and closing the incision.
 14. The method of claim13, further comprising inserting the conduit device through a defect inthe meniscal tissue.
 15. The method of claim 13, wherein loading thefirst and second conduit devices in the inserter comprises seriallyloading first and second conduit devices in the inserter.
 16. The methodof claim 13, wherein delivering biological material through the accessport of the inserter comprises delivering biological material throughthe access port of the inserter directly axially into a first terminalend of the at least one outer longitudinal channel of the first conduitdevice.
 17. The method of claim 16 further comprising deliveringbiological material from a first terminal end of the at least one outerlongitudinal channel to an opposing second terminal end of the at leastone outer longitudinal channel.
 18. The method of claim 13, whereindelivering biological material from the inserter comprises deliveringbiological material from the inserter directly axially into a firstterminal end of the at least one outer longitudinal channel of thesecond conduit device to a second terminal end of the at least one outerlongitudinal channel of the second conduit device, the first terminalend of the at least one outer longitudinal channel being co-planar witha first terminal end of the second conduit device and the secondterminal end of the at least one outer longitudinal channel beingco-planar with a second terminal end of the second conduit device.